1. Field of the Invention
The present invention relates to communications systems. More particularly, the present invention relates to controlling registration activity of a node that communicates with a network.
2. Description of Related Art and General Background
A communications system comprises a communications network and a set of nodes that communicate with the network. The communications links between the network and the nodes may be wired and/or wireless. The network may also communicate with other networks, such that a node may communicate with an entity within the network, with another node connected to the network, and/or with an entity and/or a node on another network.
One example of a communications network is a local-area network (LAN), where the network may include a set of servers and the individual nodes may include workstations, personal computers, and/or peripheral devices such as storage units and printers. Another example of a communications network is a wireless network for cellular communications, where the network may include a set of base stations and administrative units (such as mobile service controllers (MSCs) and location registers) and the individual nodes may be mobile units that communicate with the base stations over a radiolink. A mobile unit may be a cellular telephone, a wireless modem connected to a computer or other data-generating device, or a wireless local loop (WLL) station. Through the base stations, the mobile units may communicate with each other and/or with devices on other networks such as the Internet and/or the public switched telephone network (PSTN).
In some systems, a node is connected to the network through a static link. For example, the individual workstations in a wired LAN are typically connected to the network in a permanent fashion. Each node connected in such a fashion may easily be identified by the physical location of its link.
In other networks, a link between a node and the network is dynamic. In a cellular telephone network or wireless LAN, for example, the link between a mobile unit and the network does not exist when the mobile unit is not powered on. Even after a link is created, its location in the network may change as the mobile unit moves from within the range of one base station to within the range of another. Therefore, it is not possible for the network to identify a node connected in this fashion simply by the location of its link.
Several essential network functions may require the ability to identify or locate a node, however. Such functions include locating a particular node for paging purposes (e.g. to notify a cellular telephone of an incoming call) and associating an active node with a known profile for purposes such a billing, message forwarding, service differentiation, etc. Therefore, it may be very important to support such identification.
In a CDMA system for cellular communications that complies with Interim Standard-95B (or xe2x80x98IS-95B,xe2x80x99 entitled xe2x80x9cMOBILE STATION-BASE STATION COMPATIBILITY STANDARD FOR DUAL-MODE WIDEBAND SPREAD SPECTRUM CELLULAR SYSTEMS,xe2x80x9d published by the Telecommunications Industry Association/Electronics Industries Association (TIA/EIA) in Feb. 3, 1999) or Interim Standard-2000 (or xe2x80x98IS-2000,xe2x80x99 a six-part standard published by TIA/EIA July, 1999), a mobile unit is programmed with a 10-digit mobile identification number (or MIN). This number includes four digits from the mobile unit""s unique electronic serial number (ESN) and six digits from an identity token that is known to the network and is programmed into the mobile unit. Presentation of this information by the mobile unit upon communication with the network allows the network to associate the particular mobile unit with a known profile that may contain information concerning service options, billing, home area, etc. This identification mechanism also enables the network to properly route transmissions (such as incoming telephone calls) that are intended to terminate at the mobile unit. Additionally, by associating the identity token with the known profile, the network may recognize and track the mobile unit as its link moves from one base station to another.
Programming of the MIN into the mobile unit occurs during an event known as xe2x80x98provisioning.xe2x80x99 Other parameters, such as the telephone number that may be used to reach the mobile unit, may also be stored in the mobile unit during provisioning. In the past, provisioning was typically performed by the service provider before delivery of the unit to the user or, alternatively, by a retailer at the point of purchase. Recently, however, the advent of over-the-air service provisioning (or OTASP, as defined in TIA/EIA Interim Standard (IS)-683-A, entitled xe2x80x9cOVER-THE-AIR SERVICE PROVISIONING OF MOBILE STATIONS IN SPREAD SPECTRUM SYSTEMSxe2x80x9d and published in May 1998) has made it possible to postpone the provisioning operation until some time after purchase.
Mobile units that are OTASP-capable may be sold in an unprovisioned state. Before provisioning is performed, a mobile unit may originate (i.e. place) calls, but it cannot terminate calls (i.e. receive pages) because no profile for it exists within the network (for example, the unit does not yet have a telephone number). To initiate a provisioning procedure, the mobile unit queries a base station in a predetermined manner. For example, the user may use the mobile unit to initiate a call using a particular number sequence (in North America, for example, the number xe2x80x98*228xe2x80x99 has been assigned for this purpose, as indicated by the North American Numbering Plan Administration (Washington, D.C.)).
In response to a provisioning request, a base station forwards information to be stored by the mobile unit, including data relating to an identity token. Upon receiving an acknowledgement by the mobile unit that the information has been received, the base station commands the mobile unit to commit to the information (e.g. by storing it into a nonvolatile memory). After performing the commit operation, the mobile unit sends a commit acknowledgement to the network to indicate that the provisioning operation has been successfully completed.
If a commit acknowledgement is lost in transit, then the network cannot know whether the provisioning operation was completed successfully. However, the provisioned mobile unit must assume that the acknowledgement was received. In such a situation, it may happen that the mobile unit is awaiting a page from the network, while the network assumes that the mobile unit remains unprovisioned and incapable of being paged.
If the network has not yet assigned an identity token to the mobile unit, then no network identity exists for the mobile unit, and no registration attempt can succeed. In order to gain access to the network, however, the mobile unit may continue to attempt to register. Such attempts require the radio frequency (RF) transmit circuitry of the mobile unit to remain powered, thereby consuming power. Moreover, these attempts create interference in a CDMA system by adding to radiolink traffic and thereby reducing channel capacity. It is desirable to avoid these effects.
In a method according to an embodiment of the present invention, a contents of an area of a memory is received (e.g. by a processor). A registration decision is made which comprises a determination of whether the contents include an identity token. This registration decision relates to enabling a transmission of a registration message.